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BOB HIRSHON (host):
The world’s sharpest needle. I’m Bob Hirshon and this is Science Update.
Scientists have created the world’s sharpest needle. Its tip is a single atom of tungsten invisible to everything but the most powerful microscopes. Physicist Bob Wolkow (Wool-co) of the University of Alberta says they make it by exposing a normal needle made of tungsten to nitrogen gas and electricity. The gas and electricity interact with the end of the needle to pluck off atoms until there’s only one left.
ROBERT WOLKOW (University of Alberta):
It’s kind of like sculpting. In a sculpture the final shape is already in the block of stone and the sculpture knows what to take away. Well, we’re not sculptors, but we take away the atoms form the edge, leaving a tiny, tiny needle.
Since it’s so sharp, Wolkow says the needle could prove to be the best probe ever made for use in powerful electron microscopes.
I’m Bob Hirshon, for AAAS, the science society.